The present invention relates to a refractory conduit or duct assembly or connection, particularly for the transfer of molten steel from a discharge vessel such as a tundish to an ingot mold of a horizontal continuous casting plant having revolving ingot mold walls in the form of endless belts.
In the past it has been customary to use continuous casting plants for the casting of non-ferrous metal such as lead, zinc, copper and the like. Such casting plants have employed ingot molds having walls formed by cooled endless belts, whereby it was possible to obtain relatively high teeming rates of approximately 10 meters per minute. Accordingly, it was possible to obtain relatively high rates of casting, with relatively few pieces of stationary equipment. The molten metal is tranferred to the ingot mold from the tundish through an open refractory trough.
By contrast, the continuous casting of molten steel preferably occurs in vertically oscillating ingot molds into which dips, with the feeding orifice below the steel bath surface, an immersion nozzle connected vertically to the tundish and so constructed that it is airtight, thereby to prevent atmospheric air from reaching the molten steel. The maximum teeming rates are 3 to 4 meters per minute, whereby the rates of casting remain relatively low, despite the considerable amount of stationary equipment necessitated by the tundish lid.
It is however desirable to be able to employ horizontal continuous casting plants for the casting of steel bars.